US2909128A

US2909128A - Record controlled conveyor systems

Info

Publication number: US2909128A
Application number: US232989A
Authority: US
Inventors: Keen Harold Hall
Original assignee: International Computers and Tabulators Ltd
Current assignee: International Computers and Tabulators Ltd
Priority date: 1950-06-22
Filing date: 1951-06-22
Publication date: 1959-10-20
Anticipated expiration: 1976-10-20

Description

Oct. 20, 1959 Filed June 22, 195

H. H. KEEN RECORD CONTROLLED CONVEYOR SYSTEMS 6 Sheets-Sheet 1 lnvenfofi Hana/.0 firm. KEEN Mi p By Attorney Oct. 20, 1959 Filed June 22. 1951 H. H. KEEN 2,909,128

RECORD CONTROLLED CONVEYOR SYSTEMS 6 Sheets-Sheet 2 Attorney 7 Oct, 20, 1959 H. KEEN 2,909,128

RECORD CONTROLLED CONVEYOR SYSTEMS Filed June 22. 1951 6 Sheets-Sheet 3 HMOJWZPQEEN Mi. 9. H, By

Attorney Oct, 20, 1959 H. H. KEEN 2,909,128

RECORD CONTROLLED CONVEYOR SYSTEMS Filed June 22, 1951 6 Sheets-Sheet 4 os876s4s21oxY-zEFzGD T6 LIL- T8 FIG. 3.

I Inventor HIMOLD M944 KEEA/ Aftomy Oct. 20, 1959 H. H. KEEN 2,999,128

RECORD CONTROLLED CONVEYOR SYSTEMS Filed June 22, 1951 6 Sheets-Sheet 5 Inventor Hfl/POLD H041. Ma's/v M14 i Ha, r

Attorney Oct. 20, 1959 KEEN 7 2,909,128

RECORD CONTROLLED CONVEYOR SYSTEMS I v Filed June 22. 1951 Y 6 Sheets-Shet s I W T 4 (1 llllll IIHII n'" "H" A ,I ll. v

j m 2); Q 4 I03 Y 70. 1 I "In @Rfla Ill 1 I V I I09 A; 44

Ice 7 INVENTOR fin/2am f/nLL K5! AT TORNEY United States Patent 2,909,128 I RECORD CONTROLLED CONVEYOR SYSTEMS Harold Hall Keen, Letchworth, England, assi'gnor to International Computers and Tabulators Limited, London, England Application June 22, 1951, Serial No. 232,989

Claims priority, application Great Britain June 22, 1950 13 Claims. (Cl. 104-88) This invention relates to the automatic control of systems in which a plurality of items are delivered to a single conveyor.

It is common practice in the construction of a complex article to employ sub-assemblies which may be produced at widely separated points in a factory and which are transported by conveyors to a single assembly point at which they are assembled to form the completed article. For example, in the manufacture of cars it may be convenient for the sub-assemblies to comprise a chassis, an engine, a body and two axles.

There may be varieties of one or more sub-assemblies so that the sub-assemblies may be combined in several ways to provide different varieties of the final article. The axles and chassis for a car may be uniform throughout a range of vehicles, but they may be combined with a variety of engines and bodies to form the various types of vehicle within the range.

In order to avoid an excess or a deficit of a particular item occurring at the assembly point, it is desirable that the numbers of sub-assemblies fed on to the conveyor system should be determined by the number of subassemblies required to produce a single article and the total number and type of articles to be assembled.

Finally, it may be necessary to despatch from a separate store all the minor items, such as nuts and bolts, dashboard fittings etc., required for the assembling of a complete car and to arrange that they arrive at the assembly point at the same time as the related sub-assemblies. The items required will also vary with the type of car to be assembled, so that it is desirable to provide an indication at the store' for each complete set of parts put on the conveyors.

It is necessary to choose a master sub-assembly, such as the body, which will determine the minor items required and due to the layout of the conveyor system this master sub-assembly may take less time to reach the assembly point than the minor items. It is then necessary that a pre-indication be given at the stores, that is to say, the indication is given before the corresponding master sub-assembly has been put on its conveyor.

Accordingly, it is an object of the present invention to provide means for automatically controlling the selection to a commonconveyor, means for intermittently feeding record cards bearing control data, record card sensing means, means controlled by the common conveyor for rendering said card feed operative and means controlled by data sensed from the record cards for selectively operating said plurality of delivery means. J

- above the main track sections.

2,909,128 Patented Oct. 20, 1959 The invention will now be described by way of example with reference to the accompanying drawings, in which:

Figure 1 is a schematic diagram of the layout of an automatically controlled multiple conveyor system.

Figures 2A and 2B taken together show the circuits employed for controlling the item delivery apparatus.

Figure 3 is a cam timing diagram.

Figure 4 is a diagram of the control circuits of a card feeding and ejecting unit.

Fig. 5 is a diagrammatic view of a known chain conveyor trolley and track.

Fig. 6 is a diagram showing the conveyor layout in storage area 7 of Fig. 1, and

Fig. 7 is a diagrammatic view of a known card feed with sensing stations.

The invention is particularly applicable to the type of conveyor in which a track supports trolleys which are driven along the track by dogs moved by a flexible chain arranged above the trolleys.

The chain is provided with lugs which may engage with the dogs to effect driving of the trolleys. A conveyor of this type is shown and described in British Patents 428,860

x and 587,017 and 455,143.

Although type of construction is particularly suitable, other types of continuous conveyors such as those of the belt type may be employed. g

A diagrammatic view of a trolley and part of the track of a chain conveyor is shown in Fig. 5. This is of the kind shown in British Patent 455,143. A trolley 106 runs along a track formed by rails 107, and carries a downwardly projecting extension 108 adapted to support a load, represented by a carrier 153. Trolleys are driven along a main section of the track, represented in the figure by the straight section, by means of a driving chain 102. The chain is driven by any suitable means, and is supported at intervals by rollers 105 running on rails vertically The rollers are arranged in pairs and each roller is associated with a member 103 which is secured to the chain and carries a dog 104. The pairs of dogs are adapted to pivot inwardly to enable a trolley to be picked up and driven in the following way. A trolley may enter the main track from a branch track, such as 117, and waits for the approach of the next pair of dogs 104 which are driven from left to right as shown in the drawing. The leading dog pivots as it strikes the trolley and passes over it. The trailing or driving dog however, engages the end of the trolley and drives it along the main track. At this-time, however, the leading dog has passed completely over the trolley and has restored to its original position thereby providing means for preventing the trolley from running on by its own momentum or under the influence of gravity. Entry of a trolley from the branch track is under control of a releasing mechanism consisting of a diverter arm 111 and a trolley latch 120. The diverter arm is pivoted at 1-13 and maybe swung either across the branch track to make the main track continuous or across the main track as shown in the drawing, thereby providing a guide path for trolleys leaving the branch 117 to enter the main track. The movement of the diverter is controlled by a flexible Bowden, cable which, in turn, is'controlled electrically by means of a solenoid, such as magnetR33 .(Figs. 23 and 6) whose operation will be described.

A pin 114 depending from the diverter engages the forked main track, the diverter is also swung into'the position i q 7 end of. a trolley latch 120, which is pivoted at 121. Thus, when thedivert er is swung across the branch track the trolley latch also interposed across the branch and is then in a position to engage the extension 108 of a trolley traveling along the branch toward the main track. Conversely when the release mechanism is operated to withdraw the latch 120 and allow a. trolley to proceed to the ley past a point in the main track. The extension 103 on a trolley carriesapin. 1&9, and a rnicroswitch 44;is mounted beside the track in a position where it istengaged by the pin. 109. Engagement of the pin with the switch causes the switchfcontacts to be closed momentarily as the trolley passes.

. The layout of a car assembly conveyor system which will be considered by Way of example is shown diagrammatically, Figure l. Axles sire -transported from a storage area '1, to an assembly point 6 by a conveyor 8 Chassis and. engines are taken byconveyors 2; and to the assembly point 6 from storage areaszjand 3, Car bodies are transported froma storage area? by a conveyor 12.

Minutes Axle 2.7 Engine 21 Chassis Store 6 Body 3 In this case, it is necessary for the axles for a particular car to be placedon conveyor 8 first. After an interval of six minutes, the corresponding engine will be put on conveyor 10. After further intervals of three and fifteen .minutes respectively, the corresponding chassis andbody will be put on their'conveyors." This timingwill ensure 'that all thesub-assemblies arrive at the assembly point 6 7 simultaneously.

Punched record cards of known form are used to con- --trol the delivery of the various sub-assemblies to the conveyors. The planned productionfor each day is listed I in'terms of the sub-assemblies required. For each car a record card is punched, bearing the details of the subassemblies by type number. For example, the first car 7 might require a chassis, two axles, a type No. 3 engine and a type No. 2 body, and the next'vehiclemight require a chassis, twoaxles, a type No. 1 engine and a type No.1 body. These requirements would be described by five fields of a card the first of which would record the type number of the car "and four further'fields would a record details of chassis, axle, engine and body.

-- The first card has, for example, 40 punched in the first field as the type number of the car. The remaining fields are punched with the digits 1, l, 3 and 2. Since there is only one type of chassis and axle, the digit 1 will appear in the corersponding fields on all cards; For the second car, both the engine and the body are type No. 1, so that the corresponding card will be punched with, say, 40 in the car type number field, and the digit 1 in the four other fields. I In the present example, four duplicate packs are required, making a total of five packs of cards.

Similar cards are produced for each of the other cars.

we included in the production for one day, so that acornplete pack of cards represents the production for that day. Alternatively, a master file of pre punched'cards may be maintained and the required cardsselected from the file. The complete pack ofcards is now run through a tabudating machine, of known form, to obtain a list of all, the cards-contained in the pack. This list is checked against theplan'ned production to ensure that the cards are correct.

The checked pack of cards is then run througha record card reproducing machine of known form lto produce a number of .dupligatepacks; .The conveyor coutrolequipment is mainly located at a control station 4 (Figure l) which may be at any convenient point since it is linked to the sub-assembly areas only by electric cables. There are five units at the control station, each such unit comprising a card feeding mechanism, a card sensing mechanism having two sensingstations, and means for registering digital values recorded on the card. All these items are included in'well known forms of record card tabulating machines, such as thatshown and described in US; patent specification 2,174,699., to which reference may be had for a further description of parts not described in detail herein. It is convenient, therefore, to use five such tabulating machines at the control station.

.It convenient to consider .first the more complex form of control in which, for example, one out of eight body types is to be selected for delivery to the conveyor. Additionally, it will be assumed that the bodies at storage area 7,,(Figure l) are held in eight bays arranged side by side-from each of which abodyt carried by a trolley may be delivered to a position in which the trolley is picked up by the conveyor, i.e. the delivery points are spaced along a length of;the-. conveyor, and. each bay containsone type of body only.

To allow of the maximum economy of; space, the bays may be spaced-more closelyfrhan the :.distancerbetween adjacent pairs of dogs on. the conveyor, so. that. the dis- .Trolleys are released from the bays. under control of that one .of the tabulating machines at' the control. station associated with the body sub-assembly storage area. As

. shown inrFig. .7 .a tabulating machine hasa card feed ...magazine into which one of the duplicate packs of cards L 159 is placed. A card-is fed'from one end of the pack by means of a pickerknife-mechanism 151-which slides along guides 152 undercontrol ofafeed clutch magnet showndiagrammatically at 19 in Fig. 2A. a The end card ,is-thus' fed downwards by means of pairs of feeding rollers 155 alsooperated under the control of the feed clutch magnet and passed through 'afirst sensing stationhaving -a-contactroll 24 (Figs. 2A and 7) anda holder 24a carrying-sensing brushes each connected to individual plug-points 22.- Continueddownward movement of the card-causesit to pass through a second. sensing station having-a contact roll 25 and 'a-holder ZS'a-carrying a further set of sensing brushes which, as shown in Fig. 2A are each connected to individual plug points 23; These card'feeding operationsare initiated by depression of a 'tabulator drive motor M tothe other supply line 42.

In consequence, both .the feed clutch magnet 19 and the motor M' willb'ecome operative to feed 'a'card from the stack to the .first. sensing station; Make beforebreak contacts Rlb will shift to' establish a hold circuit through tabulator cam contacts T1 (Figures 2A and 3).

The card fed to the first sensings'tation will close the usual card leven contacts GL1: tofniake anlenergizing circuit fora running control relayjRZ, whichfwill establish a parallel hold circuit through contactsRZZzK-shifted) and cam contac'tsTZ -,whe'n these contacts.clo'sejustbefore ure 3, the tabulator cycle being divided up into sixteen Z index points, of which index points 9 to 0 and X and Y correspond to the time ofsensing index points on a card.

' ContactsRZa (Figure 2A) shift to'break the original energizing circuit-for'relay R1; feed clutch- 19 and'the motor, so that these will be de-energized when T1 contacts break at time. However, the clutch will remain engaged until (Figure 3), being of the well known one revolution type and the inertia of the motor and associated mechanism is suificient to assure that the machine completes one cycle each time the clutch and motor energising circuit is completed.

Relay R2 will remain energised until the last card condition is reached, when there is no card at the first sensing station, so that contacts CL1 will be open when contacts T2 open and relay R2 will be de-energised.

Since contacts R2a are now shifted, the feed clutch magnet 19 and the motor M are no longer controlled by the Start key, so that after the initial depression cards cannot be fed by accidental depression of the Start key- Cards are now fed and sensed under control of the conveyor system in order to control the release of bodies in the required order. However, in order to synchronize the operation of the tabulator with the movement of the conveyor, it is necessary to establish the time of arrival of a pair of driving dogs at the storage area. This is accomplished in the following way:

Trolleys leave the bays in the storage area loaded with bodies and are returned empty to be reloaded, switch means being provided to indicate that an empty trolley has arrived back at the storage area. The empty trolley is removed from the pair of dogs on the driving chain and these dogs are then available to pick up a loaded trolley from one of the bays. These arrangements are shown diagrammatically in Fig. 6, which shows the layout of the conveyor in the storage area 7. Empty trolleys return along the right-hand path, being driven by the chain 102, and the main trolley track turns along a path 116 out of the line of the driving chain. Thus, trolleys are turned out'of engagement with the pairs of dogs on the chain. Shortly before this disengagement takes place switch 27 is operated by the passage of a trolley in a manner similar to that described for the operation of the switches 44 as 'a trolley leavesa storage bay on a branch track 117. The distance between the switch 27 and the first bay is less than the distance between two successive pairs of dogs on the driving chain.

Contacts 27a (Fig. 2A) of the switch 27 are connected to the tabulator by wires in a cable 16 (Figure 1). This is indicated in Figure 2A by the broken line connections. If the distance between switch 27 and the tabulator is considerable, the voltage drop in cable 16 may be unduly large and it is then desirable to use a link circuit. In this case the contacts operate a relay located in storage area 7. This relay has a pair of contacts in the link circuit which may then be operated at any convenient voltage. When the contacts of this relay close, a further relay in the link circuit is energised and closes contacts which are wired in the position of contacts 27a in Figure 2A. It will be appreciated that this linking does not alter the operation of the circuit but merely obviates voltage drop in tabulator control circuit due to the length of cable 16.

When contacts 27a (Fig. 2A) of the switch 27 (Fig. 6) close, and a circuit is made from line 41 (Fig. 2A), contacts 27a (shifted), cam contacts T3, contacts RSa, feed synchronizing relay R4 to line 42, contacts T3 being closed since the tabulator stops at the 0 position (Figure 3). Relay R4 closes contacts R4b, so that a relay R5 is now energised by a circuit from line 41, contacts 27a (shifted), synchronizing interlock. relay R5, contacts R5b, contacts R4b (shifted), relay R4 to line 42. Relay R5 will shift make before ,break contacts RSb to establish a-hold circuit to line 41 and will also shift contacts R5a to break the energising circuit for'relay R4. Relay R5 will remain energised until contacts 27a remain shifted to prevent re-energisation of "relay R4 if contacts 27a should remain'closed for a period greater than that taken by the tabulator to perform one cycle.

-When relay R4 is energised-contacts R4a close to make a circuit from line 41, contacts R4a (shifted), contacts R2a (shifted), contactsRlb, relay R1, feed clutch magnet 19, drive motor M to line 42. Thus the feed clutch magnet and drive motor are operated as before, to feed a further card to the first sensing station whilst the first cardis fed to the second sensing station. Thus first the card is fed and sensed at the second station in synchronism with the conveyor operation. At this second station the required type of body will be determined and this information is'stored to cause the release of the appropriate body as the driving dogs approach the selected storage bay. a

The second sensing station which is that more remote from the card feed magazine is indicated diagrammatically by a contact roll 25 and associated brushes which are connected to individual plug sockets 23. A plug connection (not shown) is made from the particular socket 23 relating to the card column in which is punched a digit representing the body type to a plug socket 21 which is connected successively through a distributor which is driven by the main tabulator drive shaft to any one of a plurality of counter operating magnets. The counters are of the well-known electromagnetic type, in which a mechanical drive is provided for the counter wheel and the wheel may be clutched to this drive by energisation of the related counter magnet, the extent of rotation of the wheel being determined by the time in the machine cycle at which the magnet is energised.

A card lever contact CL2 will be closed by the first card in moving from the first sensing station to the second sensing station and this will complete a circuit for energising a sensing control relay R3. Contacts R31) will close to provide a hold circuit through cam contacts T2, in parallel with contacts CLZ. Relay R3 will be maintained energised by this circuit until after the last card has been sensed at the second sensing station. In the first card, in the example already considered, the digit 2 is recorded in the field relating to body type. Since there are less than ten types, this field will actually comprise only one column, and the plug connection will be made from the socket 23 corresponding to this col umn, hence at 2 time in the second cycle there will be a circuit from line 41, circuit breaker contacts CB, contacts R3c (shifted), contact roll 25, the hole in the first card in the 2 position, a sensing brush, a socket 23, a plug connection (not shown), socket 21, distributor common bar and brushes, counter magnet CR2 to line 42. The magnet CR2 will be selected since the distributor is driven by the tabulator and will be on the second segment: from the top, at 2 time. Similarly, the top segment will be. operative at 1 time, and the bottom segment at 8" time. The counter magnet CR2 on being energised will operate the related counter wheel and the usual counter cont-acts CR2a will close.

The tabulator will be arrested at 0 at the end of the second cycle and the counter contact CRZa will remain closed since, following usual practice, it is not reset until after Y time. Thus the counter contact will retain registration of the fact that a 2 has been sensed until the next card feed cycle occurs. The counter wheel is thus being used as a storage device having on and off conditions, corresponding to the closed or open state of the counter contacts. Since there are eight counter positions corresponding to the eight bays selectively operated by the distributor any digit froml to 8 may be represented by the closed state of the appropriate counter contact. No carry facilities are provided between counter Wheels so that each operates as "an individual storage device, andnot as a value accumulator.

- The closingof contacts CR2a is used to control the feeding of a type body on to the body conveyor, but

--cam contacts T (closed),

7 due to the'diiference in" spacing of theiconveyor dogs andthe delivery baysthisi'control :cannot be exercised directly. Associated with each bay is a storage device of the type shown and described in'U.S. patent specification 2,275,396, to"which reference -may be had for further description.Certain-simplifications are efle'cted in that only one setting magnet and'on'e' contact member are provided for 'eachring of'armatures; Thei'shaft, to which are secured the armature retaining 'ringsjis' driven synchronously with the conveyor so' that the shaft makes one revolution in the timeelapsingbetween the closing of the contacts27a by atrollcy driven by a dogand the same dog reaching the'end of. the eighth or'last bay.

' The contact member'for each of the storage devices is to the storage device.

The storage devices for the first three bays are shown schematically in Figure 2B, being referenced 35', 37 and 39 respectivelyi i Thus Fig. 2B shows those parts of the control apparatus which are electrically. interconnected with the tabulator circuits shown in Figf 2A but which are mechanically driven in synchronism with the main conveyordrive.

The'setting magnets

36', 38 and 40 of devices not shownare progressively staggered at- 41 intervals in the same'=way. -Thus the contact member of the eighth storagedevice is-approximately328-frorn the settingmagnet. I

-Whena dog1is a the/correct position for picking up from the"eighth-bay,-another dog will be at such a distance from switch 27 that the stud 109 (Fig. 5 of an empty trollley driven by this dog will not close the switch contacts until the storage driveshaft has rotated a further 12l= The closure of "contacts l la does not cause energisation of a setting magnet until after a delay equal to the time required forof rotation of the storage driv'e 'shaftf Since all the storage devices are synchro- -'-nisedwiththe conveyor, the relative timing as described ensures-that an energised storage magnet will always be able to set a related-armature and that the delay introduced in reading out will be such-as to ensure delivery of a trolley from achosen bay at the correct time for pick up by the-requireddri-ving dog.

When the set armature of the-storage device 37 reaches the related contact member a circuit will be made from line {41 (Figure 2B) through storage device 37, cam contacts C1, a link wire, magnet R33 to line 42. Magnet R33 is the bay release magnet for the second bay, and

onenergisation controls the delivery of a body from this bay to a point at which it is picked up by a dog on the conveyor.

' The cams operating contacts C1 are driven from the shaft driving the storage devices. The contacts are'closed the three 'storage' devices are controlled by counter contacts CRIa,CR2a and CR3a 'ina bank CR1a'to'CR8a of such'contact's (Figure 2A) respectively. 'It 'will be appreciated that five similar further storage devices are provided for the other bays and are controlled by contacts CR4a to'CR8a.

These storage devices are used to' controlthe release of bodies from each of the bays shown iii Fig. 6. The empty'trolleys' returned to the storage area travel along the track116 under the influence of gravity and are each time an armature of the related storage device passes the contact member, and they-serve to define accurately the duration of the energisation of the bay release magmanually re-loaded and moved into a stdra'ge -'bay along one of the tracks 117; the particular baybeing determined by the type of 'bodywith which the trolley is loaded; Trolleys are subsequently released, by the operation of bay release magnets R32, R33, R34 and corresponding magnets for the remaining ba'ys', Operation ofone of these magnets causes the first'trolley in the bay to be-released by the retraction of the latch 12!) '(Fig; 5). The firsttrolley in the bay then runs under the influence of-gravity toward the junction of the track 117 with the main track. Operation of the"bay release magnet also causes the movement of the diverter arm 111' into the position shown in Fig. 5 to? allow the nets when a set 'armature passes a "contact member.

1 The dog driving-- the trolley which caused the feeding of the 'first card tothe second sensingstation' and the consequent-energisation of magnet 38 will be passing in front ofthe second bay atthe-time when bay release magnet R33-is energised,"due-to the delay introduced by the card .feeding and by the-storage device 37. Consequently; the 'trolley carrying a type 2 body will be released from thesecond bay,-isautomatically-picked up by this dog and transported to the assembly point 6 (Fig ure 1).

In order to check that the operation takes place correctly, it is arranged that eachtime' a 'bodyispicked up from the second bay, a contact 44 (Figure 6) is closed.

A checking relay R28-of the mechanically latched type is in parallel "Wilih' magnet R33, so that it is energised when magnet R33=is energised: --When contacts 44 close there will be'a circuit through co'ilRQSA ,of relay R28, which willreset the relay since'coil R28A is the unlatching coil.

trolley to pass into the main track 107. "Operation of the bay release magnets will now be described.

With contactsCRZa closed 'in the manner already described, a circuit will be made from line 41" (Figure 2A) counter contacts CRZa (shifted), a plug socket 33, in a bank of plug "sockets 28 to 34, a linking connection indicated by a'broken line,

"a plug socket 47 (Figure 2B), setting magnet 38 to line 42. The relative timing of the shaft driving the storage devicesand the'conveyor is such that an armature of Subsequent'to theresetting of relay R2S;-cam contacts C2 close, but are ineffective to energise a failure-registering relay -R29 since'contactsR28a inseries therewith are open. Cam contacts C2 are operated by the same shaft as contacts C1 and close once for each'armature'passing a contactmember.

If the trolley is not released, then contacts 44' will remain open, so that relay R28 willnot be reset When contacts C2 close there will be an energising circuit for relay R29 :and a. holding circuit will be made from line 42, relay R29," contacts R29b (shifted), contacts; R2511 the storage device 37"will be in a position to be set by the energisation of magnet 38.

- The-contact member for the storage device 37 is set to line 41. ContactsR29a will close to provide a circuit to an error indicatinglarnp 50. This lamp may be located either in proximityto the bays or at the control'tabulator.

at an angular distance of approximately'82 from the setting magnet 38 in the direction 'of rotationas indicated by anarrow. .The contact member for storage-device 35 for the first bay is set approximately 4l -ahead"of--that -In' either .case,'Warning is given so that action may be taken to deal with the'failure to deliver the body. It will for the. second bay,:;whilstwthe contactmember for the third bay is approximately 41 f\beyond"that for the second bay. In this; way a successively ;greater,.delay is provided by the storagevdevices associated with

bays

1, 2 and 3. The contact members of the other storage be apparent that additional contacts of relay R29 could bewiredinto. the control circuit of amoto'ridriving the' conveyorso that the conveyor is halted if anrerror occurs.

In order to.cancel the error indication, an Error-Cancel key is depressed rto makea circuit for anerror resetting 'relay. R25. :CQDJECiSaRZSCIGlOSG to makeacircuit to the unlatching coil R28A to reset relay R28. Contacts R25a 9 open to break the hold circuit for relay R29, so that this relay is de-energised and the circuit returns to normal condition.

The complete sequence of operations for one body has now been described whereby a trolley approaching the bays causes a card to be fed in the tabulator, a counter magnet, and a storage device setting magnet and a bay release magnet to be operated in sequence and a check to be made to ensure that a trolley has been picked up by the conveyor. A similar sequence occurs each time a trolley operates the switch 27 (Fig. 6) to close contacts 27a (Fig. 2A); The control circuits for the first three bays are shown in detail, checking relays R26, R28 and R30 correspond in the three bays for example. Similarly, relays R27, R29 and R31 are operative to indicate errors in each of the three bays. The remaining five bays each have a control circuit similar to that shown for each of the first three bays.

An exactly similar arrangement of a tabulator and associated control circuits is provided to control the feeding of the various types of engines from the storage area 3 (Figure 1) on to the conveyor 10. This tabulator is also located at the control station 4 and is linked to the storage area 3 by cable 15.

Since no selection of axles or chassis is required, only one counter magnet and storage device is needed with the related tabulator. That is, the circuit is similar to that controlling the first bay in the body storage area. Cables '13 and 14 link the control tabulators for axles and chassis with their respective storage areas. The feeding of two axles for each card fed may be arranged conveniently by mounting each pair of axles on a suitable frame, so that they may be dealt with as a single unit.

At the beginning of the day, the duplicate packs of cards are placed in the feed magazines of the tabulators and the conveyors are started up in sequence. If assembly is to begin at 7 am. for example, then the axle conveyor 8 will be started first at 6.33 am. followed by the starting of

conveyors

10, 9 and 3 at 6.39 a.m., 6.42 am. and 6.57 am. respectively. It will be apparent that with this timing the sub-assemblies for the first card will all arrive at the assembly point 6 at 7 am.

It may be noted that since the conveyors are started at different times, different cards may be fed in the various control tabulators at the same instant of time. Thus the axle control tabulator may be feeding the sixth card when p the body control tabulator is feeding the first card. However, due to the delay between feeding a sub-assembly to a conveyor and arrival at the assembly point, and the fact that all the control packs are identical, the correct groupings of sub-assemblies will always be delivered to the assembly point.

It is desirable to make provision for speeding up delivery of sub-assemblies by one or more of the conveyors, so that any time loss by power supply failure, breakdowns, etc., may be regained. For this purpose, cards punched with the digit 0 in all fields are inserted in the control packs. If one of these. cards is inserted after every five control cards, for example, then one driving dog in every six on each of the conveyors will not have a trolley fed to it, since sensing of a 0 punching will not cause energisation of any of the bay release magnets.

In order to speed up delivery, when required, switches are provided to enable one, two, three or four cards punched with 0 to be fed through the tabulator sensing stations without holding up the feeding of the normal control cards. Considering the body control tabulator again, a counter magnet CRO (Figure 2A) may be made operative by inserting a plug connection when a 0 punched card is sensed at the first sensing station. A

- circuit is made at 0 time in the machine cycle from line 41, contacts CB, contacts R2c (shifted), contact roll-24, a brush sensing 0 in the card column relating to body "10 time (Figures 2A and 3), counter magnet CRO to line 42. Energisation of the counter magnet will cause counter contacts 20 to close.

Four cancel control switches SW1, SW2, SW3 and SW4 are provided to select whether 1, 2, 3 or 4' cards punched with a O should be made inefiective. It will be assumed that three cards are to be made ineffective so that switch SW3 will have been placed in the on position, and a Cancel key depressed to energise a Zero-card cancel control relay R14 through the closed key contacts and switch SW3. Contacts R1401, R1412 and R will have closed to energise three further cancel cycle control relays R21, R22 and R23 respectively. These three relays are of the mechanically latched type so that the contacts will remain in the operated position until the corresponding reset coil is energised. When the next 0-punched card arrives at the first sensing station a two-card feed control circuit consisting of relays R10 and R11 is set up to allow the O-punched card to be fed straight through the second station followed by the next body-selection card. Thus, the ineffective card cycle which would normally occur due to the passage of the O -punched card through the second sensing station does not take place since the following card is sensed immediately afterwards. The operation of the two card feed control circuit is as follows:

With relay R21 energised a circuit is made from

line

41, 0 counter contacts 20 (shifted), contacts R10b, contact R210 (shifted), relay R10 to line 42. Relay R10 shifts make before break contacts R101: to establish a hold circuit through cam contacts T8 (Figures 2A and 3).

The machine will now have stopped with a 0 punched card about to enter the second sensing station and this card will be fed through this station the next time contacts 27a close, in the manner already explained. During this subsequent cycle a relay R11 will be energised when cam contacts T7 close (Figure 3), by a circuit from line 41, cam contacts T8, contacts R1011 (shifted), contacts R210 (shifted), cam contacts T7, relay R11 to line 42. Relay R11 is of the latched type so that contacts R11b will remain closed and a parallel circuit across cam contacts T1 in the motor circuit will be provided through contacts Rllb (shifted) and contacts Rllb, R2212 and R231: (all shifted) in parallel. Cam contacts T8 open at 5 time in the cycle to de-ene rgis e relay R10, thus breaking the set up circuit for relay R11 and the counter contacts 20 are reset prior to 9 time as for the other counter contacts, so that relay R11 cannot be re-energised until contacts 20 are closed again.

Since cam contacts T1 are shunted by contacts Rllb, R2111 etc., the motor circuit is not de-energised at 2 time and in consequence a second card feed cycle occurs to feed the card following the 0 punched card through the second sensing station. Assuming that this following card is a normal control card, then it will cause selection of a body in the manner already explained. During this cycle, cam contacts T6 will close at E (Figure 3) to energise a reset coil R1111 (Figure 2A) to unlatch relay R11. This opens contacts Rllb, breaking the shunt circuit across cam contacts T1, so that the motor will be de-energised at the end of this second cycle. This two-card feed control circuit is effective for as many O-punched cards as are required under the control of cancel-cycle control relays R21 toR24 and their auxiliary. cycle relays R6 to R9, which are controlled in turn by the zero-card cancel control relays R13 to R15 and the cancel control switches SW1 to SW4. These cycle control closed from line 41, contacts Rlla. (shifted), cam contacts T4, contacts R24a, contacts R23a (shifted), a relay R7 to line 42. Relay R7 then closes contacts R712 to complete a circuit to reset coil .R23A of relay R23,= but -coil R23A is not energiseduntil contacts T40pen; since they act as a shunt across thecoil. 'When coil 'R23A is energised relay R23 is reset; since with the Cancel 'key now released relay 'R14is not energised and the set up circuit for relay R23 is inoperative.

' When the next punched card is sensed at the first sensing station, contacts 20 will again close and set up relays R and R11 to provide another double feed cycle. The circuit through contacts Rlla will energise a relay R8 to effect resetting of relay R22 in the same way as relay R7 reset relay R23.

' When the third 0 punched card is sensed a third double feed cycle will ensue and a relay'R9 'will be energised to reset relay R21, so that all the cancel circuit relays are returned to the normal position-and no more double feed cycles will occur on O punched cards being sensed until the Cancel key is again depressed.

If switches SW1, SW2, or SW4 are put in the on position, then the circuit will function as already described, except that the number of relays set up will vary. For a one card cancellation relay R21 only is operated for a two card cancellation relays R21 and R22 are operated and for a four'card cancellation relays R21, R22, R23 and R24 are operated.

It has been assumed that the O punched cards were interleaved singly with the control cards, but 'it will be apparent that if three such cards occur together for example and switch SW3 is on, then four successive feed cycles will take place to feed the three cards and the following control card through the tabulator for one closure of contacts 27.

As a further check on correct operation of the control circuit, contacts R2d and R34! are connected, in series with an error indicator lamp 26 (Figure 2A), between the

supply lines

41 and 42. If cards fail to feed from the card magazine, the card lever contacts CL]. and CL2 will open to de-energise relays R2 and R3. Contacts R2d and R3d will then be closed and the error lamp 26 will light to indicate that cards are not being fed.

So far, attention has been directed primarily to the automatic selection and feeding of the various subassemblies. In the case of the store for minor items, selection of bins containing the required items is efiected manually, so that certain modifications of the fully automatic arrangements are necessary.

It will be assumed that three different groups of minor items are held in the stores and that group 1 is used I there are only three alternative groups of items, only three counter positions are necessary.

Each counter contact is used to control operation of a card feeding and ejecting unit instead of a storage device as with the other tabulators.

The construction of these units may conveniently be similar to that shown incorporated in a record card punch in US. patent specification 2,343,414,

' to which reference may be had for a detailed description.

The circuits controlling the feedingand ejection are modified from that shown in the patent in order to operate a in conjunction with the tabulator.

A separate pack of cards is placed in the card magazine of each of the three units. The cards of each pack may bediiferentiated by being ofdiiterent colours, or may have some identification such as the group number printed thereon.

The construction and operation of each of the units ;is ..the. same, so thati'only that relating to group '2 will be described in detail. The circuit for this unit is shown in Fig. 4.

In order to bring the unit into operation, a Start key (Figure 4) is'depressed'. A circuit is thus made from carriage driving mechanism when the carriage has been returned fully to the first columnposition.

With' the carriage in the last column position, last column contacts 54 close to complete a circuit to a card ejector magnet R39. Energisation of magnet R39 causes operation of the card ejector jaws, which operation is ineffective at this time-since there is no card in the carriage. Movement of the card ejector jaws, however,

' closes contacts 53 to complete a circuit to trip magnet R35.

-T his magnet shifts latch contacts 52 to complete a circuit to a drive motor PM which operates to move the card carriage to the first column position to feed a card from 'the magazine to the carriage and to reset contacts 52,

as explained in more detail in U:S. patent specification 2,343,414.

A card lever contact '55is closed when a card isin the carriage, so that a-relayR40isnow energised by a circuit from line 41, contacts 52, contacts 55 (shifted),contacts R40b, relay R40 to line 42. Relay R40 establishes a hold circuit through shifted'make before break contacts R401). The unit will now remain with the carriage in this'position and relay R40 energised until an impulse is received from the stores control tabulator. The relay R40 is thus a supervisory relay to'indicate that the unit is ready for use. I

A connection is made between a plug socket 58 (Figure 4) and the plug socket connected to the second counter magnet contact of the stores tabulator, corresponding to socket 33 of-the' body control tabulator (Figure 2A).

'This connection which is incorporated in cable 18 (Fig.

- 1) is shown by-means ofdotted lines in Figs. 2A and 4 by way of example but it will be appreciated that since two-separate tabulators are used for storesand body control respectively, the two connections shown at socket 33 of Fig; 2A" are not, in practice, made on the same tabulator. With this-counter contact closed as a result of sensing the first card, there will be a circuit just after 1 time in the tabulator cyclewhen contacts T5 close to energise a magnet R44 (Figure 4) which is the wiper operating magnet of-a stepping switch or uniselector 61 of known form. Each energisation of magnet R44 causes the wiper to move around one contact position.

Each contact of uniselector 61 is connected to the corresponding contact position of a second uniselector 62 and a demand relay R43 isconnected between the two wipers; When the two wipers are in corresponding positions relay-R43 will be shorted out, but as long as the wipers are out of step,- then- R43 may be energised.

. Accordingly, when the wiper of uniselector 61 has moved,

' in the magazine.

relay R43 will be energised by a circuit fromline 41, contacts 56 and- R40d (both shifted) in parallel, relay R43, a resistor 63 to line 42. Contacts 56 are the usual magazine contacts'which areclosed as long as cards are Thus the operation of relay R43 indicates that a card has been demanded by the stores control tabulator.

The stores conveyor 11 (Figure 1) is of the continuous belt type and at points on the conveyor where store bins are to be placed aremounted projecting lugs. These lugs serveto-close contacts 57 (Figure 4) of switch assembly '100 mounted adjacent the conveyor and placed ahead of the loading point, as in the case of'contacts'27a.

- The-contacts 57 areconnected to the unit by means of I a cable as shown by broken lines in Fig. 4. -When contacts 57 areclosed andrelay-R43'is energised, a circuit 13 is made from line 41, contacts 57 (shifted), contacts 430 (shifted), make before break contacts R42b, contacts R38a, a card ejection control relay R42 to line 42. Contacts R4212 shift to provide a hold circuit for relay R42 via contacts 52. v

Contacts R42a close to make a circuit to the release magnet R41 through contacts R400 (shifted). Energisation of the release magnet will cause the carriage to move to the last column position, with consequent ejection of the card therein, and automatic return of the carriage to pick up the second card.

It is convenient to locate the card feed and ejection units adjacent to the conveyor, so that the ejected card falls on to the conveyor belt instead of into a card stacker. The ejected cards are carried on the conveyor past the loading point and thus provide a visual indication of the items to be selected and placed on the conveyor. Thus in the case of the stores control, the control tabulator is located in the control area 4 (Fig. 1) and the card ejecting units are located in the stores area 5 so that instead of the selection of a particular type of assembly as in the case of the body storage bays previously described, the operation of the tabulator results in the selection of an appropriate one of the card feeding and ejecting units to deliver a card to the conveyor.

The counter contacts may still be closed after the completion of this cycle and a single step control relay R45 is provided to prevent a second energisation of relay R44 due to this cause. When uniselector 61 is operated it closes a contact 59 to energise relay R45. This relay establishes a hold circuit through make before break contacts R45b which is maintained until the counter contacts open and also opens contacts R45a to break the energising circuit for relay R44.

When eject contacts 53 close to energise trip magnet R35, parallel circuits are made through contacts R40a (shifted) to energise a relay R37 and a magnet R36 which is the operating'magnet' for uniselector 62. Relay R37 closes contacts R37a to provide a shunt across contacts R40a. Energisation of magnet R36 causes the wiper of uniselector to move on to the next contact position, so that the wipers of the two uniselectors are now on corresponding contact positions and relay R43 will remain shorted out, until another card punched with a 2 is sensed. Thus the uniselector 62 is moved so that its wipers coincide with the position of the wipers of uniselector 61 only after the card which was demanded by the control tabulator has actually been delivered to the conveyor, and the demand relay R43 will therefore remain Operated until the required card has been delivered under control of the contacts 57.

The selection of the correct group of store items is governed by the type of body with which they are to be used. The times required for feeding from store area 5 (Figure 1) and body storage area 7 to the assembly point 6 are six minutes and three minutes respectively. For this reason a pre-indication is required at the stores area,.that is an indication is required of the type of body which will be fed on to conveyor 12 three minutes after the indication has been given. To effect this, the contacts corresponding to contacts 27a (Figure 2A) which control the feeding of cards in the stores control tabulator is placed on the return side of conveyor 12 (Figure 1) at such a distance from contacts 27a for the body tabulator that these first contacts are closed by a particular trolley three minutes before the same trolley closes contacts 27a. These contacts are connected to the stores tabulator by a cable 17. The two conveyors 11 and 12 are started at the same time and the pack of control cards is placed in the card magazine of the stores control tabulator, but the corresponding pack is not placed in the card magazine of the body control tabulator until three minutes later, thus ensuring. that the required relation is maintained between the feeding of the two packs.

Provision is made at assembly point 6 for holding a number of body sub-assemblies in reserve. In order to accumulate such a reserve, conveyor 12 may temporarily be run at a higher speed than the other conveyors. This will result in cards being fed in the stores control tabulator at a correspondingly increased rate, without a corresponding increase of speed in ejection of cards which is governed by the speed of conveyor 11. The two uniselectors 61 and 62 then act together to provide temporary storage of the control information. The wiper of uniselector 61 may become several contact positions ahead of that of uniselector 62. Under these conditions, successive card feeding and ejection will occur by the circuit operating in the manner described until relay R43 is once again short circuited independently of the cards being fed in the stores tabulator at that time.

a To prevent relay R42 being operated more than once for each closure of contacts 57, a single card interlock relay R38 is operated when contacts 53 close by a circuit from line 41, contacts 54 (shifted), contacts 53 (shifted), contacts R40e (shifted), contacts R38b, relay R38 to line 42. Relay R38 then establishes a hold circuit through make before break contacts R38b and contacts 57. Contacts R38a open to break the energising circuit for relay R42, so that further operation of relay R42 is prevented whilst contacts 57 are closed and maintain relay R38 energised.

If a card fails to feed into the carriage of the unit, relay R40 will not be energised. When latch contacts 52 are reset at the end of the return movement of the carriage there will be one circuit to an indicator lamp 60, through contacts R40e which will light to indicate the failure.

For convenience this invention has been described using record cards but it will be understood by those skilled in the art that record tapes bearing data are exactly equivalent and that therefore all references to record cards herein are to be deemed to include record tapes, and a record card to include a portion of a record tape.

. What I claim is:

1. In an item conveying system for assembling items on a conveyor for delivery of said items from a storage area to an assembly area in a sequential order determined by data bearing records, the combination of conveyor means moving between said item storage area and said assembly area, a plurality of item carrying means mounted at spaced points along said conveyor, a plurality of individual item storage bays forming said storage area, spaced apart along said conveyor and adjacent thereto, an item release means for each of said bays effective when operated to release an item from the associated bay for engagement with one of said item carrying means, a mechanically operated switch means adapted when operated to pass an electrical signal and mounted adjacent to the conveyor and operated by the passage of each item carrying means, a plurality of data bearing records, record sensing means for sensing said records connected in circuit with said release means, means controlled by the signal from said switch means for rendering said sensing means operative to sense successive records on successive operations of said switch means, means controlled by said sensing means for operating selectively said release means in accordance with the data sensed, and delay means also controlled by said sensing means for delaying the operation of said operating means by different periods determined by the sensed data.

2. In an item conveying system for assembling items on a conveyor for delivery of said items from a storage area to an assembly area in a sequential order determined by data bearing records, the combination of conveyor means moving between said item storage area and said assembly area, a plurality of item carrying means mounted at spaced points along said conveyor, a plurality of individual item storage bays forming said storage area, spaced apart along said conveyor and adjacent thereto, an item release means for each of said bays ef- 15 fective when operated to'release an item from the associated bay for engagementjwith'one of said item carrying means, a mechanically operated switchmeans adapted when operatedto pass an electrical signal and mounted adjacent to the conveyor and operated by the passage of each item carrying means, a plurality of data bearing records, record sensing means for sensing said records connected in circuit with said release means, a plurality of delay means, each providing a different delay period, means controlled by the signal from said switch means for rendering said sensing means operative to sense successive records on successive operations of said switch means, means operated by said sensing means forsapplying an electrical signal to one of said delay means selected in accordance with the data sensed, and means for operating selectively said release means by the delayed signal from said selected delay means.

3. In an item conveying system for assembling items on a conveyor for delivery of said items from a storage area to an assembly area in a sequential order determined by data bearing records, the combination of conveyor means moving between said item storage area and said assembly area, a plurality of item carrying means mounted at spacedpoints along said conveyor, a plurality of individual item storage bays forming said storage area, spaced apart. along said conveyor and-adjacent'thereto, an item release means for each of said bays efiectiv'e when operated to release an item from the associated bay for engagement with one of said item carrying means, a mechanically. operated switch means adapted when operated to pass an electrical signal and mounted adjacent to the conveyor and operated by the passage of each item carrying means, a plurality of data bearing records, record sensing means for sensing said records connected in circuit with said release means, means controlled by the signal from said switch means for rendering said sensing means operative to sense successiverecords on successive operations of said switch means, separate delay means for each of said release means providing a' different delay for each said item storage means, means controlled by said sensing means for selecting one of 'said delay means in agreement with the data sensed, and means for applying an operating signal to said selected delay means, whereby said'release means is operated after. adelay.

4. The combination according to claim 3 in which each of saiddelay means comprises a drum, members arranged around the periphery of said drum and settable in operative and inoperative positions, magnetic means for moving a settable member from said inoperative position to said operative position, means controlled by said sens ing means for energising said magnetic means, and second switch means operated by said member when in operative position and effective when so operatedtoactuate the associated release means.

5. In anitem conveying'system for assembling items on a conveyor for delivery of said items from a storage area to an assembly area in a sequential order determined by data bearing records, the combination of conveyor means moving between said item storage area and said assembly area, a plurality of item carrying means mounted at spaced points along said conveyor, a plurality of individual item storage bays formingsaid storage area, spaced apart along said conveyor andadjacent thereto, an item release means for each of said bays effective when operated to release an item from the associated bay for engagement with one of said. item carrying means. a mechanically operated switchmeans adapted when operated to pass an electrical signaland mounted adjacent to the conveyor and operated by the passage of each item carrying means,ra plurality of .datalbearing' records each bearing a first data item representing a selected one of said item storage means and at least one additional data item, record sensing means for sensing said records. connected in circuit with said-release means,

means controlled by the signal from said switch means meansproviding a different delayfor each said "item storage means, selector means controlled by 'said'sensing .means'for selecting the said delay meanscorresponding to said first data item sensed from said record, means for applying an operating signal through said selected delay means to the associated release means to cause release of an'itemfrom the'selecteditem storage means after a time delay, settable'control means operated by said sensing means on the'sensing of said additional data item, and. means operated by said 'control means'for initiating a further operation of said record sensing means toisense a succeeding one of said record means independently of the operation of said switch means.

6. The combination according to claim Sin which said control means is settable to a plurality of settings in each of which it isoperative for .a difierent number of successive records corresponding to said additional data item.

7. In an item conveying system for assembling'items on a conveyor for delivery of said items from a storage area to an assembly area in a sequential order determined by data bearing records, the combination ofcon- .veyor means moving between said item storage area and said assembly area, a plurality of item carrying means mounted at spaced .points along said conveyor, a plurality of individual item storage bays forming said storage area, spaced apart along said conveyor and adjacent thereto, an item release means for each of said bays effective when operated to release an item from the associated bay for engagement with one of said item carrying means, a mechanically operated switch means adapted when operated to pass an electrical signal and mounted adjacent to the conveyor and operated by thepassage of each item carrying means, a plurality of data bearing records each bearing a first data item representing a selected one of said item storage means and at least one additional data item, first and second sensing means for successively sensing said records connected in circuit with said release means, means controlled by the signal from corresponding to said firstdata item sensed from said record, and means for applying an operating signal through said selected delay means to the associated release means to cause release of an item from the item storage means after a time delay.

8. loan item conveying system, a first and second .con-

veyor. meansmovable along fixed paths for delivering items from astorage area to anassembly-area, a plurality of card feed and ejector means adjacent the-path of said 7 second conveyor means, a plurality of item carrying carrying means on the first conveyor means 1n timed remeans mounted at spaced points along said conveyor means, switch means. operable by the passage of each lation to the movement thereof, a plurality of databearing record means, record sensing means operative in response to successiveroperations of-said switch means to sense successive ones of-said record means and to generate data indicatingsignals, means responsive to'said signals selectively tocontrol operation of said card feed and ,ejectorme'ans to feed cards, in a sequence determined by the data on said record means,- on to said second conveyor means.

9. In an item conveying system, a first and second conveyor means movable along fixed paths for delivering items from a storage area to an assembly area, a plurality of card feed and ejector means adjacent, the path of said second conveyor means, a plurality of item carrying means mounted at spaced points along said conveyor means, switch means operable by the passage of each one of said carrying means on said first conveyor means, a plurality of data bearing record means, record sensing means operative in response to successive operations of said switch means to sense successive ones of said record means and to generate data-indicating signals, signal storage means operative to store signals from said sensing means, further switch means operable by the passage of each one of said carrying means on said second conveyor means in timed relation to the movement thereof, read-out means operable to read-out signals from said storage means in response to operations of said fur-. ther switch means and means responsive to the signals read-out to control selective operation of said card feeding and ejector means, in a sequence determined by the data on said record card, to feed cards on to said second conveyor means.

10. In an item conveying system for assembling items on a conveyor for delivery of said items from a storage area to an assembly area in a sequential order determined by data bearing records, the combination of conveyor means moving between said item storage area and said assembly area, a plurality of item carrying means mounted at spaced points along said conveyor, a plurality of individual item storage bays forming said storage area, spaced apart along said conveyor and adjacent thereto, an item release means for each of said bays effective when operated to release an item from the associated bay for engagement with one of said item carrying means, a mechanically operated switch means adapted when operated to pass an electrical signal and mounted adjacent to the conveyor and operated by the passage of each item carrying means, a plurality of records each bearing a data item representing one of said locations, a sensing station for sensing said records connected in circuit with said release means, feed means for feeding said records in succession through said sensing station, means controlled by the signal from said switch means for rendering operative said feed means and said sensing station for the sensing of a single record each time said switch means is operated, separate delay means for each of said release means for providing a delay appropriate to the position of the corresponding location in relation to said conveyor, selector means controlled by said sensing station for selecting a delay means corresponding to the data item sensed, and means for energising through said selected delay means the corresponding release means.

11. In an item conveying system for assembling items on a conveyor for delivery of said items from a storage area to an assembly area in a sequential order determined by data recorded on a group of record cards, the combination of a conveyor moving between said item storage area and said assembly area, a plurality of item carrying means mounted at spaced points along said conveyor, a plurality of individual item storage bays forming said storage area, spaced apart along said conveyor and adjacent thereto, a mechanically operated switch means adapted when operated to pass an electrical signal and mounted adjacent to the conveyor and operated by the passage of each item carrying means, feeding and sensing means for said record cards remotely located with respect to said conveyor and including a card hopper holding a plurality of record cards and means for vfeeding said record cards in succession past the sensing means, said feeding and sensing means being rendered operative to feed and sense a single record card in response to the signal from said switch means, an item release means for each of said bays eflective when operated to release an item from the associated bay for engagement with one of said item carrying means, control circuit means, means controlled by the card sensing means operative to activate said control circuit means for operation in accordance with the sensed data, and means effective to operate each of said item release means under the control of said control circuit means whereby each item release means is operated to release an item to that item carrying means which operated said switch means.

12. In an item conveying system for assembling items on a conveyor for delivery of said items from a storage area to an assembly area in a sequential order determined by data recorded on a group of record cards, the combination of a conveyor moving between said item storage area and said assembly area, a plurality of item carrying means mounted at spaced points along the con- 'veyor, a plurality of individual item storage bays forming said storage area, spaced apart along the conveyor and adjacent thereto, a mechanically operated switch adapted when operated to pass an electrical signal mounted adjacent to the conveyor and operated by the passage of each item carrying means, feeding and sensing means for said record cards rendered operative to feed and sense a record card by the signal from said switch, a plurality of time delay units, one for each of said bays, means controlled by the card sensing means operative to select a particular one of the delay units for operation in accordance with the sensed data, an item release means for each bay efiective when operated to release an item from the associated bay for engagement with one of said item carrying means, and means efiective to operate each item release means under control of one of the delay units, when such delay unit is operated, the time delay provided by each delay unit being such that each item release means is operated to release an item to that item carrying means which operated said switch to initiate the cycle of operation in which that item release means was selected for operation.

13. In an item conveying system as claimed in claim 12 switch means associated with each bay and switchable by an item released from that bay so as to check acceptance of released items, and adapted to reset the control circuit which efiected the particular release when so switched.

References Cited in the file of this patent UNITED STATES PATENTS 1,602,753 Davis Oct. 12, 1926 1,921,109 Webb et a1. Aug. 8, 1933 2,120,378 Tauschek June 14, 1938 2,172,756 Maschmeyer Sept. 12, 1939 2,174,699 Keen Oct. 3, 1939 2,275,396 Johnson Mar. 3, 1942 2,315,659 Russell Apr. 6, 1943 2,328,317 Wentworth Aug. 31, 1943 2,362,079 McCann et a1. Nov. 7, 1944 2,374,537 Goldsmith Apr. 24, 1945 2,611,074 Pascoe et al Sept. 16, 1952 2,630,523 Codman et 'al. Mar. 3, 1953 2,665,775 Smith Jan. 12, 1954 2,684,719 Johnson et a1. July 27, 1954